不同温度下烧结的Y211对YBCO的磁通俘获场的影响

采用顶部籽晶熔融织构法制备了YBCO准单畴块材,研究了在不同温度下烧结的Y2BaCuO5(Y211)粒子在块材中的分布及其对于磁通俘获场的影响.Y211前驱粉是通过使用氧化钇(Y2O3)、碳酸钡(BaCO3)、氧化铜(CuO)粉末在840到970℃之间煅烧制备.扫描电子显微镜(SEM)观察发现,通过900℃烧结的Y211颗粒在准单畴超导块材中的分布是均匀的.总的来说,使用性能好的Y211粉末将会降低Y211颗粒在块材的尺寸,提高了块材的磁通俘获场.在77K的温区下,直径为35mm的YBCO块材的磁通俘获场的最大值可以达到0.73T.

INFLUENCE OF THE DIFFERENT TEMPERATURES OF Y211 STARTING POWDER ON THE FLUX TRAPPED FIELD OF Y-Ba-Cu-O BULK SUPERCONDUCTOR

Single-domain Y-Ba-Cu-O(YBCO) high-temperature superconductor bulk was fabricated by top-seeding melt growth process.The distribution of the different temperatures of Y2BaCuO5(Y211) particles and its effect on the flux trapped field were investigated.Y211 starting powders were prepared by the calcinations of Y2O3,BaCO3 and CuO powders at different temperature between 840 and 970 ℃.Scan electron microscope(SEM) analysis showed that the distribution of the 900℃ of the Y211 particles presented an homogeneous character throughout the YBCO matrix.In conclusion,the employment of fine Y211 powder led to a size reduction of 211 particles in the bulk,while enhancing the flux trapped filed of the YBCO bulk.The maximum trapped field value of a large Y-Ba-Cu-O bulk sample,35mm in diameter,revealed 0.73T at 77K.